﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApp2
{
    class Class4
    {
        public int a (int a,int b){
            return a + b;
    }
        public double b(double c, double d) {
            return c + d;
        }
        public string c(string s1, string s2) {
            return s1 + s2;
        }
        public int con(int a) {
            int c = 0;
            for (int i = 0; i < a; i++)
            {
                c = c + i;
            }

            return c;
        }
    }
}
